Brilliant green sequestered poly(amic) acid film for dual-mode detection: Fluorescence and electrochemical enzymatic biosensor

• Published in: Sensors and actuators. B, Chemical Vol. 256; pp. 71 - 78
• Main Authors: Maiga, Mohomodou, Yazgan, Idris, Kariuki, Victor M., Demirkol, Dilek Odaci, Sadik, Omowunmi A., Timur, Suna
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.03.2018; Elsevier Science Ltd
• Subjects: Amperometric detection; Beverages; Biosensors; Dual-mode detection; Electrical measurement; Enzymatic sensors; Enzymes; Fluorescence; Fluorescence detection; Glucose oxidase; Glutaraldehyde; Linearity; NMR; Nuclear magnetic resonance; Oxidation; Oxygen; Poly(amic) acid; Polyamines; Quenching; Scanning electron microscopy; Enzymatic sensors; Amperometric detection; Dual-mode detection; Poly(amic) acid; Fluorescence detection
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2017.10.002

[Display omitted] •The synthesis of brilliant green sequestered poly(amic) acid film (BG-PAA).•Glucose oxidase immobilization on BG-PAA.•Glucose analysis based on consumption of oxygen in enzymatic reaction.•Dual-detection of glucose based on fluorescence and chronoamperometry.•In real samples, sensing of glucose without loss of selectivity and sensitivity and also with no need of sample preparation protocols. Herein, we report a facile technique to fabricate fluorescent polymeric structure, brilliant-green sequestered poly(amic) acid film (BG-PAA), as enzyme support-material for biosensor applications. The structure and fluorescence properties of the fabricated BG-PAA membrane were investigated using 1H NMR, scanning electron microscopy (SEM) and fluorescence microscopy. Glucose oxidase (GOx) was used as a model enzyme that immobilized on BG-PAA membrane using glutaraldehyde. The created BG-PAA/GOx membrane was utilized to fabricate dual-purpose as fluorescent and electrochemical biosensors for the determination of glucose in beverages. Utilization of the dissolved oxygen in GOx mediated glucose oxidation resulted in alteration of the measured fluorescence and current intensity. In the fluorescence assay, the decreased concentration of oxygen causes the increased fluorescence intensity due to the elimination of quenching effect of oxygen on BG fluorescence. In amperometric assay, decrease in oxygen concentration was followed at −0.7V. After optimization of working conditions linearity, limit of detection and repeatability of system were determined. Finally, BG-PAA/GOx was tested to analyze glucose in beverages.